Dental instrument.



0 H II! No. 780,147. PATENTED JAN. 17, 1905. A. A. WILGOX & M. JEWETT.

DENTAL INSTRUMENT.

APPLICATION FILED SEPT. 14. 1904.

NVE/V 4;, Miami; WM

struments,

No. 780, 1&7.

Patented January 1 '7, 1 905.

FFICE.

AMOS A. WVILCOX AND MARCELLUS JEWETT, OF CLEVELAND, OHIO.

DENTAL lNSTRUIVIENT.

SPECIFICATION forming part of Letters Patent No. 780,147, dated January17, 1905.

Application filed September 14, 1904. Serial No. 224,399.

To It whom it may concern.-

Be it known that we, AMos A. VVILoox and MARonLLUs J Ewn'r'r, citizensof the United States, and residents of Cleveland, county of Cuyahoga,and State of Ohio, have invented a new and useful Improvement in Dentalinof which the following is a specification, the principle of theinvention being herein explained and the best mode in which we havecontemplated applying that principle, so as to distinguish it from otherinventions.

Our invention relates to dental instruments, and particularly to thatclass of the latter which is adapted to force obtundent fluid or otheranesthetizing fluid through the dentine of the teeth.

Said invention consists of means hereinafter fully described, andspecifically set forth in the claims.

The annexed drawings and the following description set forth in detailcertain means enibodying the invention, such disclosed meansconstituting but one of various forms in which the principle of theinvention may be used.

In said annexed drawings, Figure 1 represents a central longitudinalsectional view of our improved instrument. Fig. 2 represents a verticaltransverse section taken upon the plane indicated by lines 2 2, Fig. 1;and Fig. 3 represents an enlarged broken perspective view of theimproved nipple used upon our dental instrument. the elastic materialsecured in the end thereof not being shown.

A hollow cylindrical casing A is provided with an integralupwardly-projecting hollow cylindrical portion B with an internalscrewthread at one end, within which a separate hollow cylindricalmember B, having an external screw-thread, is adapted to be secured, themembers B and B together forming a suitable reservoir for an obtundentor anesthetizing fluid. A piston (J is adapted to reciprocate Withinsaid reservoir, there being provided suitable packing 6 around the samewithin the reservoir, as will be noted. from the drawings. Within thecylindrical guideway a of the casing A a rack D is adapted to operate,which has connected to its rear end an upwardly-projecting car 03,having a hollow cylindrical portion d, Fig. 2, within which the end ofthe piston C is adapted to be secured, as plainly shown in Fig. 2. Itwill be noted, therefore, that the actuation of the rack l) in eitherdirection will eifect the simultaneous actuation at the same speed andin the same direction of the piston C.

The means provided for actuating the rack are as follows: Suitablyjournaled at one end in a downwardly-projecting trough-shaped portion a,secured either integrally or in 6 any other suitable manner to thecasing A and secured at the other end in a trigger wheel E, is a smallstud, forming an axis a. In the construction shown in the drawings theportion a is shown as a separate piece, secured 6 5 extended portion E,which engages with the rack D, the portion rt forming, in effect, aguard for that portion of the axis e comprising the pinion E. The pinionE is inserted within the guard at and then secured therein by means of awasher a" and screw a as shown 7 5 in Fig. 2. The trigger-wheel Ecomprises a central solid portion and a plurality of tingcr-pieces a,six, as shown, secured to said portion 1/ and shaped like triggers inorder to give a firm, easily-operable, and sensitive grip thereon. Asuitable palm-piece F for enabling the instrument to be satisfactorilyhold is secured to the casing A.

Our construction of dental instrument is an especially convenient andeffective one, as it 5 is compact and reliable, the reservoir or barrelcan be easily filled with the obtundent fluid, and the trigger-wheelenables a certain sensitiveness to pressure to be imparted to thefingers which is not present in the other con- 9 struetions of similardevices with which we are acquainted.

We have provided an improved nipple G for our dental instrument, whichis clearly shown in Fig. 3 nor enlarged portion g, adapted to receivethe externally-screw-threaded outer end of the member B of thereservoir, an outer restricted part with an enlarged portion and anintermediate tapering portion 5 Within the 100 and which comprises aninpieces and with an extended axis,

portion 9 is secured a hollow needle g registering with theliquid-passage of the nipple. The enlarged portion g is, in efiect, ahead upon the restricted portion g and is transversely slotted, as shownat g", so as to divide its upper portion into any desired number ofparts. Within the slots g thus formed is secured a flexible or resilientmaterial, thus forming an elastic point for the nipple, as shown at g,Fig. 1, whereby the nipple is rendered especially serviceable in thetreatment of teeth which are sore and tender and which could notwithstand treatment with an ordinary nipple without subjecting thepatient to unnecessary pain.

We therefore particularly point out and distinctly claim as ourinvention- 1. In a dental instrument, the combination of a two-partreservoir for liquid material; a piston operating therein; adischarge-nipple connected to said reservoir; a rack provided within anextending ear'within which said piston is secured; and a trigger-wheelprovided with aplurality of discharge-operating fingerthe lattercomprising a pinion adapted to gear with said rack.

2. In a dental instrument, a hollow casing provided with an openextending portion having an internal screw-thread; a hollow cylindricalportion provided with an external screw-thread at one end adapted toengage with the aforementioned internal screw-thread thereby providing areservoir for liquid material; a discharge-nipple connected to saidhollow cylindrical portion; a piston op erating in said reservoir; arack adapted to operate within said casing and connected to said piston;a pinion adapted to engage with said rack; and means for operating saidpinion.

3. In a dental instrument, the combination of a reservoir for liquidmaterial; a piston operating therein; a discharge-nipple connected tosaid reservoir; a casing connected to said reservoir; a rack adapted tooperate in said casing and provided with an extending ear within whichsaid piston is secured; a trigger-wheel provided with a plurality ofdischarge-operating finger-pieces and with an extended axis, said wheelbeing rigid upon said axis, the latter comprising a pinion adapted toengage with said rack; a separate portion secured to said casing adaptedto form a sheath or guard for said pinion, and providing a bearing forthe latter; and means for securing said pinion in said guard.

Signed by us this 10th day of September, 1904:.

AMOS A. VVILOOX. MARCELLUS JEWETT.

Attest:

D. T. DAVIES, G. W. SAYWELL.

